The Earth’s climate swings have disrupted human societies and civilizations throughout our species’ history; take examples like those in Jared Diamond’s Collapse. But are they also connected to one of the most famous collapses in the history books—the fall of the Roman Empire?

There are a host of reasons for the fall of Rome, researchers led by paleoclimatologist Ulf Büntgen write today in the journal Science. However, analyzing the climate records of the past 2,500 years reveals that changes to Europe’s climate coincided with the rise and fall of the famous civilization. Such a correlation could suggest that climate played some part in building the Romans up and in tearing them down.

Büntgen and colleagues collaborated with archaeologists to amass a database of more than 9,000 pieces of wood dating back 2,500 years. Samples came from both live trees and remains of buildings and other wooden artifacts, all from France and Germany. By measuring the width of annual growth rings in the wood, the researchers were able to determine temperature and precipitation levels on a year-by-year basis. [Discovery News]

The results of this unprecedented collection of climate data: In the third century B.C., when Rome fought the First and Second Punic wars against Carthage and began its ascent to Mediterranean empire, times were good. The rains fell, the temperatures were warm, and agriculture would have flourished. But by the third century A.D., the time when the Germanic invasions began to creep further into Roman territory, more droughts had come to Western Europe. This trend persisted into about the 6th century A.D.

This is no proof that changing climate caused the fall of Rome, but it’s no stretch of the imagination to think that worsening conditions could have exacerbated political divisions, invasions, and other Roman woes.

“Relatively modest changes in European climate in the past have had profound implications for society,” says Michael Mann of Penn State University in University Park, Pennsylvania. Other studies have shown how war and climate are often intimately linked. For example, periods of unusually cold weather in China during the last millennium preceded 12 of the 15 major bouts of warfare. [New Scientist]

Indeed, the very wood samples that reveal these climate trends also appear to show that productivity took a hit when the climate turned unfavorable, according to David Stahle, who wasn’t involved in this study:

By counting wood samples, the analysis also created a rough measure of human activity. In eras of prosperity, more trees were cut down for building and fuel, yielding more samples in the archaeological record. At other times, like the years after the Black Death and the so-called Migration Period between 300 C.E. and 600 C.E. when the Roman Empire was overwhelmed by tribes pushing in from the east, the number of wood samples dwindles to nearly nothing. “It’s an interesting proxy of demographic trends and really the most provocative part of the study,” says Stahle. [ScienceNOW]

Surely more studies to come will try to root out what life was like as Rome crumbled. But if Büntgen’s team has done nothing else here, Mann notes, they’ve built up a year-by-year climate record deeper into the past than anyone else, which will prove its worth in detailing the Earth’s climate shifts.

So global warming good, global cooling bad? This isn’t what billions of dollars worth of scientific research, billions of dollars worth of TV documentary, movie production and news casting, and billions of dollars worth of regulation have told us. I wonder what would happen if the growing seasons in Northern Canada and Russia were lengthened. What a catastrophe. Too bad these Carbon sharing schemes fit Karl Marx’s redistribution of wealth theories because if they didn’t we could have an honest debate about what causes climate change and not how to transfer wealth from the first world to the third world. Our scientists have been duped by the large amounts of money the Socialists have thrown at them to get the results the Socialists want.

John Lerch

Nope KJ. It has nothing to do with socialists. It’s that a LITTLE Global Cooling is Good or at least neutral and a LITTLE Global Warming is Good or neutral. A little more of either is bad. And it’s bad because there are a lot of positive feedback loops in any complex system with the result that one reaches a tipping point where a little more or either equals a LOT of either. Also abnormal causes of either are bad because we have less history to guide us.

Daniel Gooden

This is conjectural at best and not worth anyone’s time. Some of the blogs on this site have no real love of anything but suppositions.

Zachary

You’re right DG, who would have guessed that a popular science site would post articles that lead to discussion and debate. You probably complain that scholarly journals are too technical.

scott

Regardless of climate, towards the end of the roman rule Europe was stripped…its forests exhausted, rivers polluted, seaports polluted and over fished, much like we see today. It was their power and economic collapse (under a wide variety or pressures) that allowed the environment to eventually correct itself (in terms of forest regeration, etc).

Kevin – you have been watching too much FOX NEWS. And do we not have a form of “corporate communism here in the US?” – many developed areas now have the same, corporate run and owned planned developments – strip centers with the same stores, surrounded by the same house, repeated over and over. People have this idea of choice and freedom, but when they go to shop and eat, they actually are very limited in their choice, all of which are given to them by a mega corporation that runs and owns all the businesses. I was just in some areas in Texas, where everyone works and shops and eats at the same places (Wal-Mart, Target, Apples bees, etc). There are no family owned business anymore. Many of them dont have health care (and wow, fight hard to NOT have it in the name of freedom – in the name of keep the money in the Wal-Mart family). We have now, a class of ill educated worker bees who cant see past a news report on FOX.

Also…one must look at socialism and why people support it. I prefer capitalism, but..It can depend on your state of being. If you live in Venezuela and are rich and live in a luxury high rise and have a weekend house on Aruba, you hate Chavez and hate socialism and taxes. If you live in a slum, with no prospects, no running water, no schools and no services, I bet you would be voting for Chavez who would tax the rich and bring you some of those services…So, before you or anyone pop off against anything or any system, you should first entertain the ideas of how people live and why they support certain systems. If you happened to find yourself in a slum in Rio, living in hot tin shack with no water, trying to survive what system would you choose, if one was offered to you that would bring you some services (but at the expense of taxing).

s

I beleive this Blog only validates what is already known. That volcanic activity contributed greatly to the changing climate in Europe near the end of the Romans.

Reaching back into memory here, Discover already had a similar article on this….I think it was the volcano in Iceland. Combined with an earlier eruption in the South Pacific a year earlier. It was a whole cycle of eruptions in a short period of time.

As I said, I only vaguely remember it. But the findings in the wood samples used, seem to validate that there was a big shift in Europe’s climate.

badnicolez

@scott (#5) – I think you mean Caracas, not Rio. Rio is in Brazil, not Venezuela.

Also, if you don’t like the “Corporate Communism” here in the US, you should join the Tea Party and become a Libertarian. If Corporate Communism is bad, the real thing is so much worse for everyone. If those living in the slums supported free market reforms instead of a nasty dictator, their lives would be much improved. What exactly has Chavez done for the poor in Venezuela, besides causing food and power shortages?

Since we can’t possibly predict when the next major eruption will occur, how can we even remotely make a case for attempting to cool the earth on a global scale? Until the scientists can promise no major volcanic events on even a short-term scale, it would be ridiculous and dangerous in the extreme to even attempt to influence the global temperture any more than we already are.